INCOME TAXES (Deferred income taxes) (Details) - USD ($) $ in Thousands	2 Months Ended	10 Months Ended	12 Months Ended
Feb. 28, 2018	Feb. 28, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Components of the deferred tax provision or benefit
Amortization, depreciation, and basis differences for property, plant and equipment and other long-lived assets					$ 23,153	$ 21,876	$ 12,182
Amortization of intangibles					(763)	(1,030)	(3,623)
Changes in reserves for workers’ compensation, third-party casualty, and cargo claims					469	(812)	362
Revenue recognition					(2,524)	332	1,862
Allowance for doubtful accounts					(115)	(719)	(295)
Nonunion pension and other retirement plans					(2,810)	(1,977)	3,861
Multiemployer pension fund withdrawal					(5,818)
Federal net operating loss carryforwards utilized					125	28	161
State net operating loss carryforwards utilized (generated)					621	229	(304)
State depreciation adjustments					(1,761)	(1,244)	(758)
Share-based compensation					(529)	352	(681)
Valuation allowance increase (decrease)					(744)	401	(61)
Other accrued expenses					(4,881)	(852)	(4,108)
Impact of the Tax Reform Act					(3,772)	(24,542)
Other					1,221	(2,255)	924
Deferred tax provision (benefit)					$ 1,872	$ (10,213)	$ 9,522
Statutory federal rate (as a percent)	32.74%	35.00%	21.00%	32.74%	21.00%	35.00%	35.00%

-- None. No documentation exists for this element. --

No definition available.

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- Definition

Represents the amount of deferred tax provision or (benefit) on allowance for doubtful accounts during the period, due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

+ References

No definition available.

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Represents the amount of deferred tax provision or (benefit) on amortization of intangible assets arising during the period due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

+ References

No definition available.

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This element represents the amount of deferred tax provision or (benefit) on equity-based compensation costs during the period, due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

+ References

No definition available.

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Represents the deferred income tax expense benefit multiemployer pension fund withdrawal.

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No definition available.

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Represents the amount of deferred tax provision or (benefit) on domestic operating loss carryforwards during the period, due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

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No definition available.

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This element represents the amount of deferred tax provision or (benefit) on state and local operating loss carryforwards during the period, due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

+ References

No definition available.

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This element represents the amount of deferred tax provision or (benefit) on other costs not otherwise specified in the taxonomy during the period, due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

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No definition available.

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Represents the amount of deferred tax provision or (benefit) on other accrued expenses during the period, due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

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No definition available.

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This element represents the amount of deferred tax provision or (benefit) on pension and other retirement plans costs during the period, due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

+ References

No definition available.

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This element represents the amount of deferred tax provision or (benefit) on amortization, depreciation and basis difference for property, plant and equipment and other long-lived assets (excluding intangible assets) arising during the period due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

+ References

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This element represents the amount of deferred tax provision or (benefit) on changes in reserves for workers' compensation and cargo claims arising during the period due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

+ References

No definition available.

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This element represents the amount of deferred tax provision or (benefit) on revenue recognition arising during the period due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

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No definition available.

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Represents the amount of deferred tax provision or (benefit) on state depreciation adjustments during the period, due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

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This element represents the amount of deferred tax provision or (benefit) on valuation allowance during the period, due to an increase or decrease in the entity's deferred tax assets and liabilities pertaining to continuing operations.

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No definition available.

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Amount of income tax benefit for remeasurement of deferred tax liability from change in tax rate pursuant to Tax Cuts and Jobs Act of 2017.

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No definition available.

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Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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